Selective catalytic oxidation of ammonia to nitrogen over CuO/CNTs: The promoting effect of the defects of CNTs on the catalytic activity and selectivity

Abstract

CuO/CNTs were prepared as catalysts for the selective catalytic oxidation of ammonia and demonstrated high catalytic activity and N2 selectivity. The study results showed that the surface defects of carbon nanotubes (CNTs) could not only activate CuO, but also promote the electron transfer in the catalysis. Thus, along with increasing the defect density of the CNTs, the temperature for the complete ammonia oxidation could be decreased from 235°C to 189°C and the corresponding N2 selectivity increased from 93.8% to 98.7%. Moreover, there was no apparent decrease in the catalytic activity at prolonged reaction time, indicating CuO/CNT catalysts are promising for the selective catalytic oxidation of ammonia.